Cardiogenic embolism to the brain

Intracardiac Devices for Stroke Prevention

Stroke is a significant cause of serious disability and death worldwide. A substantial proportion of strokes are related to an underlying cardiac embolic source, most commonly in association with atrial arrhythmias (fibrillation/flutter). Atrial fibrillation is considered a major risk factor for stroke. Although long-term prophylactic oral anticoagulation has been shown to be very effective in reducing stroke in patients with atrial fibrillation, it has a number of major limitations and is not feasible in all patients. In such cases, the use of percutaneously (transvenous) implanted left atrial appendage occlusive devices or surgical appendage obliteration is being explored. Similarly, the presence of a patent foramen ovale, especially in the presence of an atrial septal aneurysm, is now recognized as an important potential mediator of paradoxical cardiogenic embolism. Percutaneous patent foramen ovale closure is becoming increasingly established as a safe and effective means of preventing recurrent strokes in the presence of a patent foramen ovale. In this account, the authors discuss the intracardiac devices and techniques available and the relative merits of their use for stroke prevention.

Reproducibility of Transesophageal Echocardiography in Evaluating Aortic Atheroma in Stroke Patients

Although transesophageal echocardiography (TEE) is a well-established tool in delineating the cardiac and aortic sources of emboli in stroke patients, its reproducibility in detecting aortic atherosclerosis (AA) that may lead to stroke is not well documented. The aim of this study is to demonstrate the inter- and intra-observer agreement in diagnosing AA based on the TEE study. During the study period, 2 echocardiographers read 32 TEE studies performed on a group of stroke patients. The AA was estimated by measuring the largest atheroma thickness in millimeters (mm). The intra-observers and intraclass correlation coefficients (ICC) were 0.97 and 0.85, respectively, for the 2 TEE observers. The inter-rater ICC coefficient between TEE readers was 0.91. In conclusion, TEE detected AA and defined high proportions of the morphological characteristics of atheroma with good reproducibility among inter and intra-observers.

Specific cardiac disorders in 402 consecutive patients with ischaemic cardioembolic stroke

BACKGROUND

To determine the cardiological substrate in acute stroke patients presenting with a cardioembolic stroke subtype.

METHODS

Data of 402 consecutive patients with cardioembolic stroke (cerebral infarction, n=347; transient ischaemic attack, n=55) were collected from a prospective hospital-based stroke registry in which data on 2000 stroke patients over a 10-year period were included. In all patients, specific cardiac disorders were identified by physical examination and results of electrocardiography and transthoracic echocardiography. Holter monitoring and more sensitive techniques of cardiac imaging were used in selected cases.

RESULTS

Cardioembolic cerebral ischaemia accounted for 20% of all acute strokes (25% of ischaemic cerebrovascular events). Cardiac sources of embolism included the following: (a) structural cardiac disorders associated with arrhythmia (n=232), the most frequent being left ventricular hypertrophic hypertensive disease (n=120) and rheumatic mitral valve disease (n=49); (b) structural cardiac disease with sustained sinus rhythm (n=81), the most frequent being systolic left ventricular dysfunction of both ischaemic (n=35) or non-ischaemic (n=24) aetiology; and (c) isolated atrial dysrhythmia (atrial fibrillation, n=88 and atrial flutter, n=1).

CONCLUSIONS

Hypertrophic hypertensive cardiac disease complicated with atrial fibrillation was the most frequent cardiac source of emboli in cardioembolic stroke. Other important cardiac sources were isolated atrial fibrillation, rheumatic mitral valve disease, and systolic left ventricular dysfunction of ischaemic and non-ischaemic cause. The incidence of traditional emboligenous-prone cardiac disorders, such as mitral valve prolapse and mitral annular calcification was low.

Accidents vasculaires cérébraux et néoplasie : évoquer la thrombose veineuse pulmonaire

Stroke in patients with malignant tumor are associated with various aetiologies. We report a case of lung adnocarcinoma with pulmonary vein thrombosis appending into the left atrial revealed by multiple cerebral infarcts.

Is there a place for inhaled nitric oxide in the therapy of acute pulmonary embolism?

Acute pulmonary embolism (PE) is a serious complication resulting from the migration of emboli to the lungs. Although deep venous thrombi are the most common source of emboli to the lungs, other important sources include air, amniotic fluid, fat and bone marrow. Regardless of the specific source of the emboli, very little progress has been made in the pharmacological management of this high mortality condition. Because the prognosis is linked to the degree of elevation of pulmonary vascular resistance, any therapeutic intervention to improve the hemodynamics would probably increase the low survival rate of this critical condition. Inhaled nitric oxide (iNO) has been widely tested and used in cases of pulmonary hypertension of different causes. In the last few years some authors have described beneficial effects of iNO in animal models of acute PE and in anecdotal cases of massive PE. The primary cause of death in massive PE that is caused by deep venous thrombi, gas or amniotic fluid, is acute right heart failure and circulatory shock. Increased pulmonary vascular resistance following acute PE is the cumulative result of mechanical obstruction of pulmonary vessels and pulmonary arteriolar constriction (attributable to a neurogenic reflex and to the release of vasoconstrictors). As such, the vasodilator effects of iNO could actively oppose the pulmonary hypertension following PE. This hypothesis is consistently supported by experimental studies in different animal models of PE, which demonstrated that iNO decreased (by 10 to 20%) the pulmonary artery pressure without improving pulmonary gas exchange. Although maximal vasodilatory effects are probably achieved by less than 5 parts per million iNO, which is a relatively low concentration, no dose-response study has been published so far. In addition to the animal studies, a few anecdotal reports in the literature suggest that iNO may improve the hemodynamics during acute PE. However, no prospective, controlled, randomized clinical trial addressing this issue has been conducted to date. Future investigations addressing the effects of iNO combined with other drugs such as vasoconstrictors and inhibitors of phosphodiesterase III or V, may increase the responsiveness to iNO in acute PE.

Cardiac sources of embolism should be routinely screened in ischemic colitis

OBJECTIVE

Potential cardiac sources of embolism may promote ischemic colitis. The aim of this study was to evaluate their role in segmental, nongangrenous ischemic colitis and to determine the usefulness of routine cardiac evaluation in patients with this disease.

METHODS

Sixty case and 60 control patients matched for age and gender were included and questioned regarding treatment and prior cardiovascular history or risk factors. Potential cardiac sources of embolism, classified as "proven" or " still debated," were screened using an electrocardiogram, rhythmic Holter monitoring over 24 h, and transthoracic echocardiography.

RESULTS

Sex ratio (male:female) was 1:2, and mean age was 70 +/- 14 yr. Case and control patients had similar drug use, prior cardiovascular history, and risk factors. A potential cardiac source of embolism was found in 26/60 case (43%), compared with 14/60 control patients (23%) (p = 0.02; OR = 2.5, 95% CI = 1.2-5.5). Excluding the "still debated," 21/60 case (35%), compared with 8/60 control patients (13%), had a "proven" cardiac source of embolism (p < 0.01; OR = 3.5, 95% CI = 1.4-8.4). Electrocardiogram alone misdiagnosed 72% of the "proven" cardiac sources of embolism, whereas the combination electrocardiogram plus Holter monitoring detected 71%, and electrocardiogram plus echocardiography 62%. Twelve of 21 case patients with at least one proven cardiac source of embolism, were previously unknown. Anticoagulant therapy was required in 32% of case patients and antiarrhythmic therapy in 25% of cases.

CONCLUSIONS

Potential cardiac sources of embolism were more common in patients with segmental, nongangrenous ischemic colitis than in control patients. Therefore, these patients should undergo a routine electrocardiogram, rhythmic Holter monitoring, and transthoracic echocardiography. Anticoagulant therapy should also be considered for this patient population.

Stroke owing to noncompaction of myocardium

Noncompaction of myocardium is a rare and recently defined entity that may cause cardioembolism during childhood. We report an 18-month-old girl with noncompaction of the left ventricular myocardium presenting with fatal cardioembolic stroke. The patient had a high factor VIII level, which is known to cause an increased tendency to thromboembolic events. To our knowledge, this is the youngest case with stroke associated with noncompaction of the myocardium. Patients with noncompaction should be considered for prophylactic antithrombotic treatment to prevent mortality and morbidity owing to systemic thromboembolic events, especially if they carry additional risk factors that make them prone to hypercoagulation.

The role of the atria in congenital heart disease

The atria play an important role in adult congenital heart disease. Atrial function is often altered due to longstanding pressure or volume overload. Cardiac surgery inflicts lasting damage to the atria, which leads to loss of atrial compliance. Both the history of atrial overload and the atrial scarring form substrates for atrial tachycardias. There has been a growing interest in the interatrial septum in the past few years. There is evidence for a role of the persisting foramen ovale and atrial septal aneurysm as a causative or permissive factor in cerebral stroke. Catheter closure of the PFO may be an attractive option, especially for younger patients.

Transoesophageal echocardiography in selecting patients for anticoagulation after ischaemic stroke or transient ischaemic attack

OBJECTIVES

To investigate prospectively the role of transoesophageal echocardiography (TEE) in selecting patients for anticoagulation in an unselected stroke population.

METHODS

Transthoracic echocardiography (TTE) and TEE were done in all clinically suitable hospitalised patients (n = 457) with transient ischaemic attack or ischaemic stroke in the acute phase during a two year period in Turku University Hospital. 441 patients were successfully evaluated for cardiac sources of embolism using TEE within 31 days of the event.

RESULTS

A major risk factor for a cardiac source of embolism excluding atrial fibrillation, acute myocardial infarction, and prosthetic valve was detected in 10% of patients and a minor risk factor for a cardiac source of embolism in 46%. When a major risk factor of a cardiac source of embolism was detected using TTE or TEE and no contraindications were present, the patient was given anticoagulation drugs. If a minor risk factor for a cardiac source of embolism was detected, anticoagulation treatment was started after clinical assessment, if no contraindications were present. In 62 (14%) cases, the patient was given oral anticoagulation drugs or the necessity of ongoing anticoagulation treatment was confirmed on the basis of TEE. When these anticoagulation treated patients were evaluated using logistic regression analysis, they were found to have significantly more atrial fibrillation and histories of myocardial infarctions. Moreover, the patients were mainly men. When patients in sinus rhythm and without any history of cardiac disease were analysed, 8% of patients were found to have been given anticoagulation drugs on the basis of TEE data.

CONCLUSION

This study suggests that TEE should be used in patients with stroke even without any clinical evidence of cardiac disease when the patients are candidates for anticoagulation.

Transesophageal and transthoracic echocardiography and Doppler-examinations in systemic lupus erythematosus

OBJECTIVE

To search for cardiac abnormalities in systemic lupus erythematosus (SLE).

METHODS

35 patients examined by 2-D transthoracal Doppler and transesophageal echocardiography.

RESULTS

Mitral and aortic valve abnormalities were seen in 12 patients (34%) respectively, and occurred altogether in 16 patients (46%). They were in general significantly associated with longer disease duration, but not with anticardiolipin antibodies (aCL), disease activity, or any other variable, except for time on corticosteroids. which was significantly longer in patients with aortic valve calcifications.

CONCLUSION

Valve masses and valve thickening--often in combination--are the most frequent structural findings in SLE, occurring more often on the aortic than on the mitral valves. Factors other than antiphospholipid antibodies, medication, hypertension, or coronary heart disease seem to be responsible for this phenomenon. Drugs that modulate inflammation in endo- and pericardial tissue may, at least in part, be responsible for the observed mitral valve calcifications and pericardial fibrosis.

[Cerebrovascular diseases in patients aged 15 to 40 years: neuropathological findings in 47 cases]

Cerebrovascular diseases in patients between 15 and 40 years old are not a frequent subject in Latin-American literature, especially when focusing on neuropathology. We analyzed 47 brains from necropsies performed from 1987 to 1997 and selected on a basis of age and the presence of vascular pathology. From the 47 analyzed brains, 26 belonged to females (55.3%). When distributed among age groups, 12.8% (n=6) affected patients from 15 to 20 yo, 51,1% (n=24) from 21 to 30 yo, 36,2% (n=17) from 31 to 40 yo. The underlying diseases were: cardiac and haemathologic (19.2%), pregnancy complications (12.76%), infections, diseases of blood vessels and neurological (10.1% each) amongst others. The neuropathological abnormalities included cerebral and/or cerebellar herniation (16%), cerebral edema (13.8%), subarachnoid hemorrhage (10%), recent cerebral infarction (9%), intraparenchymatous hemorrhage (8.14%), hypoxic-ischemic encephalopathy (3%) and other events such as Sneddon syndrome and Lupus vasculitis. These findings express that the cerebrovascular phenomena in this age group are unique and closely related with the underlying disease.

Patent foramen ovale closure in patients with transient ischemia attack/stroke

Paradoxical embolism through a patent foramen ovale (PFO) has been recognized as a potential cause of transient ischemia attack (TIA) and stroke especially in younger patients. The therapeutic options are medical treatment (antiaggregation or anticoagulation) with an annual recurrence rate of 3% to 4% for stroke or TIA, surgical PFO closure, or catheter closure. Randomized studies are ongoing; however, the results will not be available soon. Since August 1994, we have attempted catheter closure of a PFO in 281 patients (age 17 to 79 years, mean 46.8 +/- 13.2) with paradoxical embolism. Of these, 184 patients had at least one embolic stroke, 112 patients at least one TIA, and 15 patients at least one peripheral embolism. The diameter of the PFO, measured with a balloon catheter, ranged from 3 mm to 24 mm with a mean of 10 +/- 3.5 mm. Implantation of the occluder was technically successful in all patients (two attempts in four patients). Seven different devices were used: 26 Sideris buttoned, 11 ASDOS, 19 Angel Wings, 98 PFO-Star, 37 Cardioseal-Starflex, 57 Amplatzer and, 33 Helex devices. One patient suffered from septicemia and subsequently died. In 2 patients, device embolization occurred during or after the procedure (1 Sideris, 1 PFO-Star; catheter retrieval successful). Thirty-seven patients had other minor complications without long-term sequelae: atrial fibrillation within the first weeks after implantation in five patients, asymptomatic thrombus on the device at routine transesophageal echocardiogram (TEE) in 7 patients (1 Angel Wings, 1 ASDOS, 1 CardioSeal, 4 PFO-Star), and device frame fracture in 25 patients (2 Sideris, 4 ASDOS, 1 Angel Wings, 1 CardioSeal, 17 PFO-Star). No complications occurred with the newer devices (Amplatzer and Helex). A residual shunt after 6 months was found in 5.5% of the patients who had completed their 6-month TEE follow-up. In two patients, a second occluder was implanted because of a residual shunt. During a follow-up period of 1 month to 71 months (mean 12 +/- 16 months, 268 patient years), a recurrence of an embolic event (seven TIA, two stroke) occurred in eight patients. None of these occurred with the newer devices (Amplatzer, Helex). Freedom from recurrence of the combined end point of TIA, ischemic stroke, and peripheral embolism was 95.7% (95% CI: 89.0%-98.4%) at 1 year and 94.1% (95% CI: 80.1-98.4%) at 3 years. Catheter PFO closure is a technically simple procedure. With the newer devices and increasing experience, the success rate has improved and the complication rate has decreased. The advantage of the procedure is that closing the defect means a causal treatment. However, catheter closure of PFO despite a very low morbidity has inherent potential risks like any other interventional procedure. Furthermore, selection of patients who definitely have PFO as the cause of their cerebral event has not been defined. For these reasons, further studies are warranted.

Catheter closure of the persistent foramen ovale: mid-term results in 162 patients

Four different types of occluder systems were used to close a persistent foramen ovale (PFO) in 162 patients with paradoxical embolic events. Ninety-eight patients had ischemic stroke, 60 transient ischemic attacks (TIA) or prolonged reversible ischemic neurological deficit (PRIND), and 4 had peripheral arterial embolism. The age of the patients was 40.2 +/- 11.9 years and the ischemic event had happened 7 +/- 10 months before device closure. CardioSeal and Amplatzer occluders were the most commonly used devices (73 and 77 cases, respectively). Implantations were successful in all patients. Serious catheter-related complications included two device embolizations and two venous bleedings. Six patients had documented supraventricular arrhythmias within the first month after implantation, which disappeared spontaneously within some weeks without therapy in three patients; the other three patients with atrial fibrillation needed conversion to sinus rhythm. Residual leaks were found in 5 out of 116 patients who had been followed by transesophageal echocardiography (TEE) and one leak was closed by a second device. During a follow-up period of 19.4 +/- 16.2 months per patient, TIA and PRIND occurred in 3 of 116 patients. Interventional closure of PFO is a simple, effective and quick method that is superior to surgery and avoids the problems of life-long anticoagulation.

Safety and cost of low-molecular-weight heparin as bridging anticoagulant therapy in subacute cerebral ischemia

BACKGROUND AND PURPOSE

Anticoagulation with intravenous unfractionated heparin (IVUH) while awaiting therapeutic oral anticoagulant levels is a common practice in patients with acute and subacute cerebral ischemia. A promising alternative strategy is to use bridging subcutaneous low-molecular-weight heparin (LMWH), which may have a favorable risk-benefit profile compared with IVUH and may permit earlier discharge with completion of transition to warfarin therapy as an outpatient.

METHODS

A LMWH, enoxaparin 1 mg/kg BID, was used as bridging anticoagulation therapy in 24 consecutive patients admitted to a university stroke center in whom the treatment plan included transition from acute to chronic anticoagulation. The LMWH group was contrasted with the preceding 24 patients transitioned to warfarin with IVUH at the same center.

RESULTS

Fewer patients in the LMWH bridging therapy group experienced neurological worsening than in the IVUH bridging therapy group (2/24 versus 8/24; P:=0.033). Fewer total adverse events were noted in the LMWH group than in the IVUH cohort (3 versus 20; P:=0. 002). Fifteen of the 24 LMWH patients (62.5%) were discharged while still receiving LMWH and completed transition to warfarin as outpatients, receiving an average of 3.6 days of outpatient transitional therapy. In these 15 patients, use of LMWH was associated with a net savings of $2197 per patient.

CONCLUSIONS

In this pilot cohort with subacute cerebral ischemia, bridging LMWH appeared to be safer than bridging IVUH and was associated with reduced hospital stay and reduced total cost of care.

Use of oral anticoagulants in older patients

Recently published American and British guidelines have comprehensively reviewed the indications for long term anticoagulation. The best evidence currently available supports the use of long term oral anticoagulants in patients with nonvalvular atrial fibrillation (NVAF), venous thromboembolic disease, ischaemic heart disease, mural thrombi, and mechanical heart valves. Selected patients with valvular heart disease, cerebral vascular disease, and peripheral arterial disease may also benefit from the use of these drugs. When no specific contraindications are present, elderly patients with either paroxysmal or persistent NVAF should be considered candidates for treatment with anticoagulants. Pooled analyses of the results from 9 randomised trials demonstrate that warfarin significantly reduces the risk of ischaemic stroke in patients with NVAF, particularly those in a 'high risk' category defined by the presence of additional clinical or echocardiographic risk factors. Long term anticoagulation does not appear to be justified in patients with NVAF considered to be at 'low risk' for stroke. Because the prevalence of NVAF and most other cardiovascular conditions increases with advancing age, many elderly patients will be candidates for thromboprophylaxis. The potential benefit of long term anticoagulation must be carefully weighed against the risk of serious haemorrhage in such patients. Bleeding complications with anticoagulant drugs appear to occur more frequently in older patients than in younger individuals. Advanced age (>75 years), intensity of anticoagulation [International Normalised Ratio (INR) >4.0], history of cerebral vascular disease (recent or remote), and concomitant use of drugs that interfere with haemostasis [aspirin (acetylsalicylic acid) or nonsteroidal anti-inflammatory drugs] are among the most important variables in determining an individual's risk for major bleeding with anticoagulants. Older patients often display increased sensitivity to the effects of warfarin, both in the early induction phase and during the long term maintenance phase of therapy. Conditions such as congestive heart failure, malignancy, malnutrition, diarrhoea and unsuspected vitamin K deficiency, enhance the prothrombin time response. The decision to interrupt anticoagulant therapy before elective surgery in elderly patients should evaluate the thrombotic risk of such a manoeuvre versus the risk of bleeding if anticoagulants are continued. In non-surgical patients, excessively elevated INRs without associated haemorrhage can usually be managed by simply witholding one or several doses of warfarin. If more rapid reversal is needed, small doses of phytomenadione (vitamin K1) can be administered safely without overcorrection or the development of vitamin K-induced warfarin resistance.

Atrial fibrillation and stroke: clinical presentation of cardioembolic versus atherothrombotic infarction

The aim of the study was to compare demographic characteristics, anamnestic findings, cerebrovascular risk factors, and clinical and neuroimaging data of cardioembolic stroke patients with and without atrial fibrillation and of atherothrombotic stroke patients with and without atrial fibrillation. Predictors of early diagnosis of cardioembolic vs. atherothrombotic stroke infarction in atrial fibrillation patients were also determined. Data of cardioembolic stroke patients with (n=266) and without (n=81) atrial fibrillation and of atherothrombotic stroke patients with (n=75) and without (n=377) were obtained from 2000 consecutive patients included in the prospective Sagrat Cor-Alianza Hospital of Barcelona Stroke Registry. Risk factors, clinical characteristics and neuroimaging features in these subgroups were compared. The independent predictive value of each variable on early diagnosis of stroke subtype was assessed with a logistic regression analysis. In-hospital mortality in patients with atrial fibrillation was significantly higher than in non-atrial fibrillation patients both in cardioembolic (32.6% vs. 14.8%, P<0. 005) and atherothrombotic stroke (29.3% vs. 18.8%, P<0.04). Valvular heart disease (odds ratio (OR) 4.6; 95% confidence interval (95% CI) 1.19-17.68) and sudden onset (OR 1.8; 95% CI 0.97-3.63) were predictors of cardioembolic stroke, and subacute onset (OR 8; 95% CI 1.29-49.42), COPD (OR 5.2; 95% CI 1.91-14.21), hypertension (OR 3. 63; 95% CI 1.92-6.85), hypercholesterolemia (OR 2.67; 95% CI 1.13-6. 28), transient ischaemic attack (OR 2.49; 95% CI 1.05-5.90), ischaemic heart disease (OR 2.30; 95% CI 1.15-4.60) and diabetes (OR 2.26; 95% CI 1.14-4.47) of atherothrombotic stroke. In conclusion, some clinical features at stroke onset may help clinicians to differentiate cerebral infarction subtypes in patients with atrial fibrillation. Atrial fibrillation is associated with a higher in-hospital mortality both in cardioembolic and atherothrombotic stroke patients.

Recent heavy drinking of alcohol and embolic stroke

BACKGROUND AND PURPOSE

Epidemiological evidence suggests that heavy alcohol consumption increases the risk for ischemic stroke, whereas light-to-moderate alcohol intake decreases the risk, but the role of different drinking patterns has remained unclear. We investigated recent light, moderate, and heavy alcohol drinking and former heavy drinking as risk factors for acute ischemic brain infarction by etiological subtype of stroke.

METHODS

We compared 212 consecutive patients aged between 16 and 60 years, who were completely evaluated for the etiology of their ischemic stroke, with 274 control subjects admitted to the emergency unit of the same hospital. ORs, as estimates of multivariate relative risks (RRs), and 95% CIs after adjustment for possible confounding variables were calculated by logistic regression. The ORs were adjusted for age, sex, body mass index, hypertension, diabetes, hyperlipemia, current smoking, and history of migraine.

RESULTS

Recent heavy drinking but not former heavy drinking was an independent risk factor for stroke (RR 1.82, 95% CI 1.08 to 3.05). Consumption of 151 to 300 g and >300 g alcohol within the week preceding the onset of stroke significantly increased the risk for cardioembolic and cryptogenic stroke. Consumption of >40 g alcohol within the preceding 24 hours increased the risk for cardiogenic embolism to the brain among those who had a high-risk source (RR 4.75, 95% CI 1.23 to 18.4), the risk for tandem embolism among those who had prominent large-artery atherosclerosis (RR 7.68, 95% CI 1.82 to 32.3), and the risk for cryptogenic stroke (RR 3.84, 95% CI 1.69 to 8.71). Light drinking did not increase the risk for stroke.

CONCLUSIONS

We conclude that acute drinking of intoxicating amounts of alcohol may trigger the onset of embolic stroke among subjects who have a source of thrombus in the heart or the large arteries.

Impact of long-term ECG recording on the detection of paroxysmal atrial fibrillation in patients after an acute ischemic stroke

An ECG recording time of 24 hours has a low yield to detect atrial arrhythmias in patients after an acute ischemic stroke. The present study investigated whether a recording time of 72 instead of 24 hours detects paroxysmal atrial fibrillation in more patients. The study prospectively included 82 consecutive patients 2-3 weeks after an acute ischemic stroke. All patients had sinus rhythm in the resting ECGs and no history of atrial fibrillation or flutter. The frequency of atrial fibrillation was assessed after 24, 48, and 72 hours of ambulatory ECG monitoring. An ECG monitoring time of 72 hours documented paroxysmal atrial fibrillation in five (6%) patients. The episode of paroxysmal atrial fibrillation occurred in only one patient within 24 hours. The other patients had their first episode of atrial fibrillation between 24 and 48 hours (n = 2) and between 48 and 72 hours (n = 2). These five patients were older (age = 70 +/- 5 years), whereas the mean age of the remaining patients was 59 +/- 13 years. All five patients had cardiovascular disease in comparison to 36 of 77 patients and reported palpitations in comparison to 6 of 77 of the remaining patients. In conclusion, ambulatory ECG monitoring over 72 hours detected after the first recording day four of five patients in whom paroxysmal atrial fibrillation could be documented for the first time. The 72-hour recording time improved, compared to the 24-hour period, the detection of paroxysmal atrial fibrillation in patients after an ischemic stroke. It seems to be more efficient to perform prolonged ECG recording mainly in older patients with a cardiovascular disease and/or a history of palpitations.

Superselective Intra-Arterial Thrombolysis for Acute Cardioembolic Stroke in a Child with Idiopathic Dilated Cardiomyopathy

We describe a case of cardioembolic dominant hemisphere internal carotid artery occlusion in a child with idiopathic dilated cardiomyopathy. The patient was subjected to superselective local intra-arterial thrombolysis using recombinant tissue plasminogen activator (Alteplase; Actilyse®). In presence of good collateral flow local intra-arterial thrombolysis prevented a major dominant hemisphere ischaemic stroke, although post-interventional computed tomographic scans disclosed haemorrhagic conversion in the left corpus striatum. Forty eight months after ischaemic stroke and thrombolysis the patient is ambulatory with a moderate neurologic deficit.

Ischemic stroke. Impact of a recent myocardial infarction

BACKGROUND AND PURPOSE

The risk of ischemic stroke is increased after a myocardial infarction. We quantified the stroke risk and evaluated ischemic stroke characteristics after an acute myocardial infarction.

METHODS

A case-control study including patients with first-ever stroke was undertaken. Cases (n=103) were recorded prospectively in the population-based Northern Sweden World Health Organization Multinational Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study. Two controls per case with a stroke but without a recent myocardial infarction were matched for age, sex, and year of stroke onset.

RESULTS

The sudden onset of neurological symptoms (76.7% versus 54.9%, P<0.001), impairment of consciousness (35.0% versus 18.4%, P<0.01), and a progression in neurological deficits (19.4% versus 8.7%, P<0.01) were more common in cases, while the onset of stroke during sleep was rarer in cases (6.8% versus 21.4%, P<0.01). In cases and controls, the clinical subclasses of stroke were as follows: total anterior circulation infarcts, 51.5% versus 37.9% (P<0.05); partial anterior circulation infarcts, 28.2% versus 26.7% (P=NS); lacunar infarcts, 4.8% versus 27.2% (P<0.001); and posterior circulation infarcts, 15.5% versus 8.2% (P=0.051). During the first 28 days after myocardial infarction, the daily rate of stroke declined rapidly from approximately 9 to 1 stroke per 10 000 myocardial infarction patients compared with an age-adjusted average daily stroke rate of 0.14 per 10 000 in the MONICA population.

CONCLUSIONS

We conclude that the clinical characteristics of the stroke differ between patients with and without a recent myocardial infarction. The risk of a first-ever ischemic stroke is highest during the first few days after a myocardial infarction, but it then declines rapidly, and the absolute number of stroke events is low.

Role of echocardiography in systemic arterial embolism. A review with recommendations

The ability of echocardiography to diagnose sources of embolism and the role of the examination in the prediction of thromboembolism are reviewed. In addition, the yield of transthoracic (TTE) and transoesophageal echocardiography (TEE) is analysed in patients with suspected embolism and guidelines are proposed for performing echocardiography in this setting. In general, echocardiography is reliable for diagnosing sources of embolism and this applies in particular to TEE in the case of atrial, valvular, and aortic abnormalities. However, the method is useful for predicting embolism in a few cases only. There is a substantial risk in the event of mobile or protruding thrombi, but screening for these and other markers of thromboembolism seems to be unproductive in most groups of risk patients. Yet, in the presence of atrial fibrillation, echocardiography may be helpful in defining patients with an otherwise normal heart and low risk of embolism--and in defining the relatively rare patient with a clinically low-risk profile but moderate-to-severe left ventricular systolic dysfunction and a high risk of embolism. TEE-guided conversion of atrial fibrillation without weeks of preceding anticoagulation may prove useful, after further investigation. The risk of embolism in relation to the size and mobility of valvular vegetations has remained controversial. In patients with suspected recent embolism, TTE results in less than 5% new therapeutic consequences. In those with a normal TTE, the yield of TEE seems to be equally low. We therefore recommend a selective strategy: TTE and TEE can be omitted when a cardiac source of embolism appears from the clinical setting and in most patients with an obvious predisposition to cerebrovascular disease. However, in the latter cases TTE should be performed if indicated by the clinical situation, e.g. in the presence of fever and murmur. TTE is also recommended when there are no obvious markers of primary vascular disease. To preclude very rare sources of embolism (e.g. atrial thrombi despite sinus rhythm), supplementary TEE is recommended in younger patients in whom primary vascular disease is very unlikely. The diagnosis by TEE of common conditions such as atrial septal aneurysms and patent foramen ovale cannot, however, be taken as proof of the mechanism of a systemic arterial occlusive event; thus it is difficult to change therapy on the basis of such diagnoses.

Right- and left-sided interatrial septal aneurysm mimicking atrial tumor and stroke

We report the cases of two patients with cerebral embolization and interatrial septal aneurysm. Transesophageal echocardiography required for stroke showed right-sided interatrial septal aneurysm in the first patient and left-sided interatrial septal aneurysm in the second. In the two patients, interatrial septal aneurysm was mimicking atrial cystic tumor or abscess. Significant internal carotid artery stenosis was found in the first patient and aortic arch atheroma with mobile components but no patent foramen ovale in the second patient. In the two patients, interatrial septal aneurysm appears to be only an incidental finding and not the true cause of stroke. Furthermore, we discuss the differential diagnoses of atrial masses.

Detection of patent foramen ovale by transcranial Doppler and carotid duplex ultrasonography: a comparison with transoesophageal echocardiography

Patients who have suffered a transient ischaemic attack or minor stroke are examined thoroughly to determine the aetiology of the cerebrovascular incident. An examination of the carotid arteries is compulsory to detect significant stenosis. In some patients, cardiogenic sources of emboli may be suspected. This study examined the possibilities of screening for patent foramen ovale (PFO) using i.v. injection of a microbubble solution with Doppler monitoring of the internal carotid artery (ICA) and the middle cerebral artery (MCA). Transoesophageal echocardiography (TEE) served as the gold standard. Twenty-three patients with a recent episode of cerebral ischaemia were examined: 12 patients with and 11 without PFO documented by TEE. After i.v. injection, microbubbles were monitored visually in the right and left atria and using Doppler sonography in the right ICA and in the right MCA. In the group with a PFO (n = 12), microbubbles were detected in the ICA in seven patients (7 of 12) and in the MCA in 10 patients (10 of 10). In the group without a PFO, microbubbles were detected in the ICA in one patient and in the MCA in two. This corresponds to a sensitivity and specificity, respectively, of 58% and 91% for the ICA/duplex technique and 100% and 82% for the MCA/transcranial Doppler technique. From this limited sample, it is shown that transcranial Doppler monitoring of the middle cerebral artery, but not ultrasound duplex monitoring of the internal carotid artery, can be used as screening for patent foramen ovale.

Patent foramen ovale size and embolic brain imaging findings among patients with ischemic stroke

BACKGROUND AND PURPOSE

Although the cause of stroke among patients with patent foramen ovale (PFO) may be due to paradoxical cerebral embolism (PCE), this mechanism is often difficult to prove. The aim of our study was to evaluate the association between brain imaging findings suggestive of embolism and PFO among ischemic stroke patients.

METHODS

As part of the Northern Manhattan Stroke Study, 95 patients with first ischemic stroke over age 39 underwent transesophageal echocardiography (TEE) for evaluation of a cardiac source of embolism. The stroke subtype was determined by modified NINDS Stroke Data Bank criteria. Stroke subtype and MRI/CT imaging data were evaluated blind to the presence of a PFO. These findings were compared between two groups: patients with medium to large PFO (> or =2 mm) and small (<2 mm) or no PFO.

RESULTS

Of the 95 patients who underwent TEE, 31 (33%) had a PFO. The frequency of PFO was significantly greater among patients with cryptogenic infarcts (19 of 42; 45%) compared with patients with determined cause of stroke (12 of 53, 23%; P=0.02). Medium to large PFOs were found more often among cryptogenic strokes than among infarcts of determined cause (26% versus 6%; P=0.04). Superficial infarcts occurred more often in the group with larger PFOs than in the group with small or no PFOs (50% versus 21%; P=0.02). Patients with medium or large PFOs more frequently had occipital and infratentorial strokes (57% versus 27%; P=0.02).

CONCLUSIONS

Stroke patients with larger PFOs show more brain imaging features of embolic infarcts than those with small PFOs. Larger PFOs may be more likely to cause paradoxical embolization and may help explain the stroke mechanism among patients with no other definite cause.

Cardiac changes in stroke patients and controls evaluated with transoesophageal echocardiography

In stroke patients several cardiac changes associated with embolism can be detected with transoesophageal echocardiography. Potential major cardiac embolic sources (e.g. atrial fibrillation, thrombi of left ventricle/atrium, vegetation, myxoma, dilated cardiomyopathy) have a causal relationship to embolism. Other changes with no certain causal relationship are regarded as potential minor cardiac embolic sources (e.g. atrial septal aneurysm, patent foramen ovale, mitral annular calcification, mitral valve prolapse, protruding atheroma of the aorta). We compared the prevalences of major and minor potential cardiac embolic sources in a stroke population with that in controls. One hundred and twenty-one patients with first-ever stroke were compared with 68 randomly selected controls. All subjects underwent magnetic resonance imaging of the brain, carotid ultrasound and transthoracic/transoesophageal echocardiography. The patients were slightly older (mean age 70.7 +/- 10.3 years) than the controls (65.5 +/- 15.5 years) (p < 0.05). Potential major cardiac embolic sources were found in 27% of the patients and in 4% of the controls (p < 0.001). The most common major potential embolic source was atrial fibrillation, detected in 22/121 patients. Fifteen of these also had spontaneous echocontrast in the left atrium. Eleven left atrial thrombi were found (four of these patients had atrial fibrillation and seven had sinus rhythm). A history of heart disease was more common in patients with a potential major cardiac embolic source or a carotid artery stenosis (77%) than in those patients without (44%) (p < 0.01). After excluding subjects with a major potential cardiac embolic source and/or carotid artery stenosis, no differences in the prevalence of minor potential cardiac embolic sources were found between patients (55%) and control subjects (47%) (p = NS). Even when subjects without a major potential cardiac embolic source or a carotid artery stenosis were categorized into three age groups (35-54, 55-74 and > 74 years) the prevalence of potential minor cardiac embolic sources did not differ between patients and controls. To conclude, major potential cardiac embolic sources are more common in an older population with first-ever stroke than in a comparable control group. However, potential minor cardiac embolic sources did not differ in prevalence in the patients compared with controls. Certain changes (e.g. atrial septal aneurysm) might have a potential embolic role in younger stroke patients but in our study no difference was found between older stroke patients and controls.

Sensorimotor stroke; clinical features, MRI findings, and cardiac and vascular concomitants in 32 patients

BACKGROUND AND PURPOSE

Sensorimotor stroke (SMS) is often included among the lacunar syndromes, although the underlying cause of this stroke-subtype is less well documented. To this end we analysed 32 patients presenting with a sensorimotor syndrome.

METHODS

The study protocol included vascular risk factors, echocardiography, Doppler sonography of carotid arteries, CT scan and MRI of the brain.

RESULTS

There were 23 men and 9 women, mean age 65.7 years. Hypertension was present in 28% and diabetes in 19%. In all, 63% had sensorimotor deficit of faciobrachiocrural areas and 37% had faciobrachial or brachiocrural deficits. MRI disclosed a presumably relevant infarct in 26 patients (81%); 20 patients (62%) localized to the territory of small perforating arteries, 3 patients (9.5%) in the internal borderzone, and 3 patients (9.5%) in cortical territories. Eight of 20 deep infarcts were larger than 15 mm. No hemorrhage or non-vascular lesion was found. A potential cardioembolic source was present in 5 patients (16%), whereas 2 patients (6%) had an ipsilateral carotid stenosis >50%.

CONCLUSIONS

Small vessel disease was the most likely cause in 69% of our patients with SMS, whereas 31% had a potential cardioembolic source, large artery disease or infarcts not compatible with perforating artery disease.

Cardioembolic infarction in the Sagrat Cor-Alianza Hospital of Barcelona Stroke Registry

OBJECTIVES

To describe the clinical features of cardioembolic infarcts.

MATERIAL & METHODS

Cardioembolic infarct was diagnosed in 231 (15.4%) of 1500 consecutive stroke patients included in a prospective stroke registry over an 8-year period.

RESULTS

Cardiac sources of emboli included isolated atrial dysrhythmia (57.1%), valvular heart disease (20.3%), and coronary artery disease (18.2%). Patients with cardioembolic stroke showed a significantly higher (P < 0.00001) frequency of sudden onset of neurological deficit (79.7%) and altered consciousness (31.2%) than patients with lacunar infarct (38% and 1.9%) and atherothrombotic infarction (46% and 24%). Eleven patients had a spectacular shrinking deficit and 6 a presumed cardioembolic lacunar infarct. Early recurrent embolisms occurred in 6.5% of patients mostly (60%) within 7 days of initial embolism. In-hospital mortality was 27.3% (0.8% in lacunar infarcts, 21.7% in atherothrombotic infarction, P < 0.00001).

CONCLUSION

Cardioembolic infarction is a severe subtype of stroke with a high risk of early death. Clinical features at stroke onset may help clinicians to differentiate cerebral infarction subtypes and to establish prognosis more accurately.

Vascular effects of statins in stroke

BACKGROUND

Recent clinical trials and meta-analyses of beta-hydroxy-beta-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have demonstrated a reduction in ischemic stroke in patients with a history of coronary artery disease both with and without elevations of serum cholesterol. This review summarizes clinical trials of these compounds and their recent impact on stroke and explores the underlying vascular mechanisms of their actions.

SUMMARY OF REVIEW

Use of statins in patients with vascular disease has been shown to lower the incidence of stroke by approximately 30%. Statins exhibit a number of antiatherosclerotic and antithrombotic properties that likely underlie the recently observed reductions in cerebrovascular disease. Statins reduce inflammatory, proliferative, and thrombogenic processes in plaque, making it less likely to rupture. Additionally, they reverse the endothelial dysfunction and platelet activation accompanying hypercholesterolemia and may reduce the tendency to thrombosis.

CONCLUSIONS

Hypercholesterolemia has reemerged as a risk factor for ischemic stroke. Statins protect against thromboembolic stroke through multiple beneficial effects within the vascular milieu. Further data are awaited to support the growing importance of cholesterol as a risk factor for ischemic stroke and the benefits of statin therapy in patients with cerebrovascular disease.

Comparison of frequency of left atrial thrombus in patients with mechanical prosthetic cardiac valves and stroke versus transient ischemic attacks

Transesophageal echocardiography performed in a group of 36 patients who had a first cerebral embolic event after implantation of a mechanical cardiac valvular prosthesis revealed that stroke is associated with the presence of left atrial thrombi more frequently than transient ischemic attacks. Intracardiac embolic sources other than thrombi are possibly related more often to the latter type of cerebral embolism in this patient population.

Carotid floating plaques associated with multiple cerebral embolic strokes. Case reports

The authors describe 2 patients with multiple cerebral infarcts and hemorrhagic transformation caused by artery-to-artery emboli. Ulcerated plaques with free-floating thrombus adherent to the plaque were detected at the carotid bifurcation by duplex sonography. No other embolic source could be found. One patient developed an occipital infarction due to carotid emboli passing through a fetal-type posterior communicating artery. Both patients recovered well without recurrence of stroke or transient ischemic attack with antiplatelet treatment only. Follow-up carotid duplex sonography showed disappearance of floating thrombus in 1 patient and consolidation of the lesion in the other.

Thrombogenesis in mitral regurgitation and aortic stenosis

The exact mechanisms for thrombus formation in patients with valvular heart disease have not been clearly defined. Abnormalities in plasma coagulation factors indicative of a prothrombotic state may in part account for the risk of stroke and thromboembolism in such patients. The aim of this study was, therefore, to determine the effects of mitral regurgitation (MR) and aortic stenosis (AS) on plasma fibrinogen or fibrin D-dimer levels as indices of a thrombogenic (or prothrombotic) state. A total of 25 patients with valve disease in sinus rhythm were studied: 12 patients (all women; mean age fifty-five years, sem 3.3) with MR; and 13 patients (7 men, 6 women; mean age fifty-seven years, sem 3.5) with AS were studied. Patients with MR had a median plasma fibrinogen that was significantly elevated when compared with female population values (median difference 0.62 g/L; 95% confidence intervals (CI) 0.27 to 1.05, P = 0.0016). However, these patients had a median plasma fibrin D-dimer that was lower than that for population controls (median difference 21 ng/mL; 95% CI 0 to 38, P = 0.05). Patients with aortic valve disease had a median plasma fibrinogen that was significantly increased when compared with population controls (median difference 0.82 g/L; 95% CI 0.34 to 1.24, P = 0.001). These patients had a plasma fibrin D-dimer level that was similar to population values (median difference 3 ng/mL; 95% CI -25 to 22, P = 0.80). Patients with MR or AS have higher plasma fibrinogen levels when compared with "normal" population values, suggesting possible hemorheologic abnormalities in these patients. Subjects with MR had lower plasma fibrin D-dimer levels, suggesting lesser intravascular clotting, consistent with clinical echocardiographic studies. Subjects with AS had plasma fibrin D-dimer levels similar to the "normal" population values, suggestive of a different pathophysiological mechanism for thromboembolism. These findings add to an improved understanding of the relationship between clinical observations and the significance of plasma fibrinogen and fibrin D-dimer levels in thrombogenesis.

Utilization of echocardiography by internists and cardiologists: a comparative study

OBJECTIVE

To compare the utilization of echocardiography as a diagnostic tool by internists and cardiologists.

DESIGN

Retrospective study.

SETTING

Tertiary care university hospital.

METHODS

Indications and clinical utility of echocardiographic studies ordered by cardiologists (group A, n = 301) and internists (group B, n = 297) were compared by chart review. The two groups of patients were analyzed to determine if the studies detected new cardiac pathology and/or altered patient management.

RESULTS

The proportion of studies with abnormal results were similar in both groups (19% versus 14%, P > 0.05). The results of echocardiography, however, led to a change in management more often when the study was ordered by cardiologists (16% versus 10%, P < 0.05). A significantly greater proportion of studies were ordered for evaluation of valvular function by internists (44% versus 33%, P < 0.05). Echocardiography detected valvular abnormalities in a similar proportion of cases in groups A and B (14% versus 10%, P > 0.05). However, diagnostic yield was very poor when the study was performed in patients with suspected mitral valve prolapse in both groups. Cardiologists utilized echocardiography more often for evaluation of left ventricular function (35% versus 18%, P < 0.01) and in the setting of atherosclerotic heart disease for detecting wall motion abnormalities (14% versus 5%, P < 0.01).

CONCLUSION

Diagnostic yield of echocardiography is similar when ordered by internists and cardiologists. With the information obtained, management is altered in a slightly greater proportion of cases involving a cardiologist. This may be due to utilization of echocardiography more often for estimating left ventricular function and for detecting wall motion abnormalities by cardiologists.

Cerebral infarction in patients aged 15 to 40 years

BACKGROUND AND PURPOSE

Cerebral infarction among young adults has been little studied in Brazil. Most studies adopt a variable upper age limit and often use the term "young" to designate different age ranges. The objective of the present study was to determine possible differences in etiology of cerebral infarction in specific age subpopulations.

METHODS

We studied 106 patients aged 15 to 40 years and divided them into two subpopulations by age at time of ictus (ie, 15 to 29 years and 30 to 40 years). On the basis of Trial of ORG 10172 in Acute Stroke Treatment (TOAST) criteria, we classified the patients into the following five groups: (1) large-artery atherosclerosis, (2) small-vessel occlusion or lacunae, (3) cardioembolism, (4) other determined causes, and (5) undetermined causes. The proportions for each group were compared between the two age ranges to determine whether there was a significant difference in group distribution.

RESULTS

The proportions were different between the two age ranges, with a predominance of women and TOAST-criterion group 4 in the 15- to 29-year age range. In the 30- to 40-year age range, there was a predominance of men and of TOAST-criterion group 3.

CONCLUSIONS

The proportions of the groups in the two age ranges were significantly different for lacunar infarctions and infarctions of other etiologies. This observation suggests that different age ranges present characteristically different distributions and therefore should be considered separately when investigated. The older age range already presents features that suggest a transition to the spectrum observed among the aged.

Embolic thrombus on mitral anulus calcification

Embolic thrombus on mitral anulus calcification (MAC) was demonstrated in an 83-year-old woman with retinal embolism. Mitral anulus calcification has been associated with a significant increase of stroke in elderly people. Atrial fibrillation and calcific emboli have been reported, and embolic thrombus by MAC may be another potential cause.

Race and sex differences in the distribution of cerebral atherosclerosis

BACKGROUND AND PURPOSE

The purpose of this study was to assess the influence of race, sex, and other risk factors on the location of atherosclerotic occlusive lesions in cerebral vessels. Previous angiographic studies of patients with stroke or transient ischemic attack (TIA) suggest that extracranial atherosclerosis is more common in whites and intracranial disease is more common in blacks. Noninvasive techniques such as duplex ultrasound, transcranial Doppler (TCD), and magnetic resonance angiography (MRA) allow vascular assessment of a more representative proportion of patients than does conventional angiography alone.

METHODS

Consecutive patients evaluated at a community hospital for stroke or TIA over a 2-year period were reviewed. Lesions were defined as a 50% or greater atherosclerotic stenosis by angiography, duplex ultrasound, or TCD, or a moderate stenosis by MRA.

RESULTS

Whites were more likely than blacks to have extracranial carotid artery lesions (33% versus 15%, P = .001), but the proportion of patients with intracranial lesions was similar (24% versus 22%). Men were more likely to have intracranial lesions than women (29% versus 14%, P = .03). When multivariate logistic regression analysis was used, white race was the only predictor for extracranial carotid artery lesions, and male sex was the only predictor for intracranial lesions. The cause of stroke/TIA was extracranial carotid artery disease in 8% and intracranial disease in 8% of all patients in the study.

CONCLUSIONS

The distribution of cerebral atherosclerosis is influenced by race and sex but not by other vascular risk factors. In our patient population, intracranial disease is as common a cause of cerebral ischemia as extracranial carotid disease.

Basilar artery blood flow during head rotation in vertebrobasilar ischemia

PATIENTS AND METHODS

Forty-six patients with vertebrobasilar ischemia and 40 control subjects were examined during head rotation using transcranial Doppler ultrasonography.

RESULTS

In the control group, no difference in blood flow velocity through the BA was found between the neutral and rotated positions. Based on these data, a blood flow reduction in the BA of more than 20% was considered to be significantly abnormal (p < 0.01). In three of 46 patients no signal was detectable in the BA using TCD. The reduction in blood flow velocity through the BA during head rotation was strongly dependent on the condition of the VA; none of 23 patients without atherosclerotic lesions or hypoplasia of the VA developed a significant reduction in blood flow through the BA. Two of 11 patients with unilateral VA lesions had significantly reduced blood flow in the BA (27% and 31%), although both were asymptomatic. Five of nine patients with bilateral VA lesions showed a significant reduction in blood flow through the BA (mean = 52%, minimum = 30%), and four of these developed clinical symptoms such as vertigo or diplopia during the rotation maneuver.

CONCLUSION

These data suggest that patients with uni- or bilateral lesions of the VA are at risk for developing clinically relevant reductions in blood flow through the BA during head rotation. Because not all patients with VA lesions developed reduced blood flow velocity, we conclude that individual vascular mechanisms must play an important compensatory role.

Atrial septal aneurysm plus a patent foramen ovale. A predisposing factor for paradoxical embolism and refractory hypoxemia during pulmonary embolism

We report three consecutive cases of patients who had refractory hypoxemia and paradoxical embolism during the course of pulmonary embolism. Transesophageal echocardiography showed an atrial septal aneurysm and a patent foramen ovale in all patients. The latter was detected by an early and massive passage of contrast from the right to the left atrium. We suggest that the presence of an atrial septal aneurysm plus a patent foramen ovale greatly enhances both magnitude of shunting and the risk of systemic embolism. The presence of an atrial septal aneurysm plus a patent foramen ovale should be considered and checked using transesophageal echocardiography in every patient with significant pulmonary embolism.

Anticoagulant treatment in primary health care in Finland

OBJECTIVE

To establish the prevalence of anticoagulant (AC) treatment, the indications, and the quality of care in primary health care.

DESIGN

A cross-sectional study, in which patients on AC treatment were identified from laboratory records. The main and second indications for AC treatment and the last value of the AC-test were taken from medical records.

SETTING

Eight Finnish health centres with a total population of 182091 inhabitants.

RESULTS

A total of 1255 patients on AC treatment were identified, 48% of them men. The mean age was 68.9 years. The age-adjusted prevalence of AC treatment was 0.65%. The commonest main indication was atrial fibrillation (38%). It was the main or second indication in 591 patients (age-adjusted prevalence 0.30%). The next commonest main indication was deep vein thrombosis (15%), followed by pulmonary embolism (8%). A total of 274 (22%) patients were anticoagulated for cerebral circulatory disturbances. 86% of the latest prothrombin time values fell within recommended ranges.

CONCLUSION

The prevalence of AC treatment in Finland seems to be high. The proportion of patients with atrial fibrillation is high, differing from the results in other countries. The monitoring of AC-treatment as the general practitioner's responsibility functions well. The quality of care is good, even in older age groups.

Aneurysm of the left sinus of Valsalva. An unusual source of cerebral embolism

BACKGROUND

Aneurysm of the ascending aorta is rarely reported as the source of emboli. We report a patient with a minor stroke in whom a saccular aneurysm of the left sinus of Valsalva was diagnosed as the presumed source of cerebral embolism.

CASE DESCRIPTION

A 49-year-old right-handed woman presented 10 days after sudden onset of right-sided hemiparesis. Her history was uneventful apart from an acute inflammation of the subcutaneous tissue in the right leg 20 years earlier. A diastolic murmur was heard best over the third left intercostal space. Results of duplex ultrasound investigation of the cerebral vessels, chest x-ray, and electrocardiography and biochemical and hematological variables were normal. CT of the brain showed a small hypodense area in the left frontal region. Transthoracic and transesophageal echocardiography detected moderate aortic regurgitation and a saccular aneurysm originating from the left sinus of Valsalva. The aneurysm had calcified walls and contained thrombotic material. Surgical closure of the aneurysm with a pericardial patch was performed to prevent recurrent embolism and rupture. Coaptation of the aortic valves was achieved, and no residual aortic regurgitation could be detected.

CONCLUSIONS

We conclude that an unruptured sinus of Valsalva aneurysm should be included in the list of sources of embolism. Transthoracic echocardiography establishes the diagnosis. Transesophageal echocardiography provides additional information about the origin and size of the aneurysm and presence of thrombotic material. Surgical closure of the aneurysm prevents rupture and recurrent embolism and possibly corrects aortic regurgitation.

Plasma beta-hexosaminidase isoenzymes A and B in patients with cerebral infarction

We determined plasma activity of the isoenzymes of beta-hexosaminidase (Hex) in 151 patients with cerebral infarction, since earlier findings have shown a relation between Hex isoenzymes and risk factors for vascular disease in normal subjects. Compared with 206 control subjects, an elevated level of plasma Hex isoenzymes was found in patients with cerebral infarction, particularly females. However, there was no relation to the clinical subtypes of diagnosis or to the presence of any risk factors for vascular disease, such as carotid artery stenosis, major potential cardio-embolic risk factors on echocardiography, hypertension, heart disease, diabetes mellitus or tobacco smoking. Instead, our findings indicate that Hex isoenzymes in patients with cerebral infarction are more influenced by the level of serum aspartate aminotransferase and blood glucose. The main conclusion is that the liver function as reflected by the level of liver enzymes and glucose metabolism are the major determinants of Hex isoenzymes in plasma.

Paradoxical embolism in the presence of right-to-left shunt due to tricuspid occlusion

The case of a 33-year-old woman suffering from a paradoxical peripheral embolism in the presence of a right-to-left shunt at the level of an ostium secundum defect is presented. A functional stenosis of the tricuspid valve due to obstruction through a thrombotic atrial mass was found to be responsible for the right-to-left shunt. Treatment consisted of peripheral embolectomy, removal of the atrial mass, and closure of the atrial septum defect.

Prevalence of intraatrial thrombus in patients with atrial flutter

In summary, left atrial thrombus occurs with disproportionately high frequency in patients hospitalized with atrial flutter. Male gender and a left ventricular ejection fraction < 40% are predictors of left atrial thrombus formation in such patients.